528 AGRICULTURAL ANALYSIS 



analyzed at the Colorado station the percentages of moisture in 

 the leaf varied from 6.08 to 28.00, and those of ash from 22.60 to 

 28.OO. 19 The percentages of potash in the ash varied from 15.20 

 to 26.30. In these data the carbon dioxid, sand, etc., are included 

 while in those quoted from the Connecticut station they are ex- 

 cluded. 



447. Cottonseed Hulls and Meal. A considerable quantity of 

 potash is added to the soil in cottonseed meal and hulls. The 

 practice of burning the hulls cannot be recommended, although 

 it is frequently done, for the incineration does not increase 

 the quantities of phosphoric acid and potash, while it destroys 

 the availability of the nitrogen. Nevertheless, the analyst will 

 often have to deal with samples of the raw materials above men- 

 tioned, as well as with the ash of the hulls, in which the potash 

 can be determined by some one of the standard methods to be 

 described. In general it is found that the hulls of seeds and the 

 bark and leaves of plants have a greater percentage of ash 

 than the interior portions. In the case of cottonseed, how- 

 ever, an exception is to be noted. The cottonseed meal in the 

 air-dried state has about seven per cent, of ash, while the hulls 

 have only about three. When it is remembered, however, that 

 the greater part of the oil has been removed from the meal it will 

 be seen that in the whole seed in the fresh state the discrepancy 

 is not so marked. 



In the crude ash of the hulls the percentage of potash varies 

 generally from 20 to 25, but in numerous cases these 

 limits are exceeded. In 12 samples of cottonseed hull ashes 

 examined by the Connecticut station the mean percentage of 

 potash in the crude sample was 22.47, anc ^ tne extremes 15.57 

 and 30.24 per cent., respectively. 20 In determining the value of 

 the ash per ton the content of phosphoric acid must also be taken 

 into account. 



Cottonseed meal contains about 1.75 per cent of potash. Since 

 the mean percentage of ash in the meal is seven, the mean con- 

 tent of potash in the crude ash is about 25. 



19 Colorado Agricultural Experiment Station, Bulletin 10, 1890 : 13. 

 w Connecticut Agricultural Experiment Station, Bulletin 103, 1890 : 9. 



